feat: add warning log to notifier if execution client is offline

packages/beacon-node/src/execution/engine/disabled.ts

@@ -1,6 +1,8 @@
 import {ExecutionEngineState, IExecutionEngine, PayloadIdCache} from "./interface.js";
 
 export class ExecutionEngineDisabled implements IExecutionEngine {
+  state = ExecutionEngineState.OFFLINE;
+
   readonly payloadIdCache = new PayloadIdCache();
 
   async notifyNewPayload(): Promise<never> {
@@ -26,8 +28,4 @@ export class ExecutionEngineDisabled implements IExecutionEngine {
   getPayloadBodiesByRange(): Promise<never> {
     throw Error("Execution engine disabled");
   }
-
-  getState(): ExecutionEngineState {
-    throw Error("Execution engine disabled");
-  }
 }

packages/beacon-node/src/execution/engine/http.ts

@@ -103,7 +103,7 @@ export class ExecutionEngineHttp implements IExecutionEngine {
   // The default state is ONLINE, it will be updated to SYNCING once we receive the first payload
   // This assumption is better than the OFFLINE state, since we can't be sure if the EL is offline and being offline may trigger some notifications
   // It's safer to to avoid false positives and assume that the EL is syncing until we receive the first payload
-  private state: ExecutionEngineState = ExecutionEngineState.ONLINE;
+  state: ExecutionEngineState = ExecutionEngineState.ONLINE;
 
   readonly payloadIdCache = new PayloadIdCache();
   /**
@@ -417,10 +417,6 @@ export class ExecutionEngineHttp implements IExecutionEngine {
     return response.map(deserializeExecutionPayloadBody);
   }
 
-  getState(): ExecutionEngineState {
-    return this.state;
-  }
-
   private updateEngineState(newState: ExecutionEngineState): void {
     const oldState = this.state;
 

packages/beacon-node/src/execution/engine/interface.ts

@@ -89,6 +89,8 @@ export type VersionedHashes = Uint8Array[];
  * - Integrated code into the same binary
  */
 export interface IExecutionEngine {
+  readonly state: ExecutionEngineState;
+
   payloadIdCache: PayloadIdCache;
   /**
    * A state transition function which applies changes to the self.execution_state.
@@ -146,6 +148,4 @@ export interface IExecutionEngine {
   getPayloadBodiesByHash(blockHash: DATA[]): Promise<(ExecutionPayloadBody | null)[]>;
 
   getPayloadBodiesByRange(start: number, count: number): Promise<(ExecutionPayloadBody | null)[]>;
-
-  getState(): ExecutionEngineState;
 }

packages/beacon-node/src/node/notifier.ts

@@ -1,10 +1,11 @@
 import {BeaconConfig} from "@lodestar/config";
 import {Epoch} from "@lodestar/types";
-import {CachedBeaconStateAllForks} from "@lodestar/state-transition";
+import {CachedBeaconStateAllForks, computeStartSlotAtEpoch} from "@lodestar/state-transition";
 import {ProtoBlock, ExecutionStatus} from "@lodestar/fork-choice";
 import {ErrorAborted, Logger, sleep, prettyBytes, prettyBytesShort} from "@lodestar/utils";
 import {EPOCHS_PER_SYNC_COMMITTEE_PERIOD, SLOTS_PER_EPOCH} from "@lodestar/params";
 import {computeEpochAtSlot, isExecutionCachedStateType, isMergeTransitionComplete} from "@lodestar/state-transition";
+import {ExecutionEngineState} from "../execution/index.js";
 import {IBeaconChain} from "../chain/index.js";
 import {INetwork} from "../network/index.js";
 import {IBeaconSync, SyncState} from "../sync/index.js";
@@ -53,6 +54,14 @@ export async function runNodeNotifier(modules: NodeNotifierModules): Promise<voi
       const clockSlot = chain.clock.currentSlot;
       const clockEpoch = computeEpochAtSlot(clockSlot);
 
+      if (
+        clockEpoch >= config.BELLATRIX_FORK_EPOCH &&
+        computeStartSlotAtEpoch(clockEpoch) === clockSlot &&
+        chain.executionEngine.state === ExecutionEngineState.OFFLINE
+      ) {
+        logger.warn("Execution client is offline");
+      }
+
       const headInfo = chain.forkChoice.getHead();
       const headState = chain.getHeadState();
       const finalizedEpoch = headState.finalizedCheckpoint.epoch;

packages/beacon-node/src/sync/sync.ts

@@ -88,7 +88,7 @@ export class BeaconSync implements IBeaconSync {
 
   getSyncStatus(): SyncingStatus {
     const currentSlot = this.chain.clock.currentSlot;
-    const elOffline = this.chain.executionEngine.getState() === ExecutionEngineState.OFFLINE;
+    const elOffline = this.chain.executionEngine.state === ExecutionEngineState.OFFLINE;
 
     // If we are pre/at genesis, signal ready
     if (currentSlot <= GENESIS_SLOT) {